16ca19ffc5
stength reduce my previous patch a bit. The only instructions
...
that are allowed to have metadata operands are intrinsic calls,
and the only ones that take metadata currently return void.
Just reject all void instructions, which should not be value
numbered anyway. To future proof things, add an assert to the
getHashValue impl for calls to check that metadata operands
aren't present.
llvm-svn: 122759
2011-01-03 18:43:03 +00:00
142f1cd251
fix PR8895: metadata operands don't have a strong use of their
...
nested values, so they can change and drop to null, which can
change the hash and cause havok.
It turns out that it isn't a good idea to value number stuff
with metadata operands anyway, so... don't.
llvm-svn: 122758
2011-01-03 18:28:15 +00:00
697de77339
Speed up instsimplify by about 10-15% by not bothering to retry
...
InstructionSimplify on instructions that didn't change since the
last time round the loop.
llvm-svn: 122745
2011-01-03 10:50:04 +00:00
43cecb1200
Switch a worklist in CodeGenPrepare to SmallVector and increase the inline
...
capacity on the Visited SmallPtrSet. On 403.gcc, this is about a 4.5% speedup of
CodeGenPrepare time (which itself is 10% of time spent in the backend).
This is progress towards PR8889.
llvm-svn: 122741
2011-01-03 06:33:01 +00:00
9e5e9ed79a
earlycse can do trivial with-a-block dead store
...
elimination as well. This deletes 60 stores in 176.gcc
that largely come from bitfield code.
llvm-svn: 122736
2011-01-03 04:17:24 +00:00
4b9a525742
switch the load table to use a recycling bump pointer allocator,
...
speeding earlycse up by 6%.
llvm-svn: 122733
2011-01-03 03:53:50 +00:00
e0e32a9ef0
now that loads are in their own table, we can implement
...
store->load forwarding. This allows EarlyCSE to zap 600 more
loads from 176.gcc.
llvm-svn: 122732
2011-01-03 03:46:34 +00:00
92bb0f9f9d
split loads and calls into separate tables. Loads are now just indexed
...
by their pointer instead of using MemoryValue to wrap it.
llvm-svn: 122731
2011-01-03 03:41:27 +00:00
4cb365414f
various cleanups, no functionality change.
...
llvm-svn: 122729
2011-01-03 03:28:23 +00:00
b9a8efc960
Teach EarlyCSE to do trivial CSE of loads and read-only calls.
...
On 176.gcc, this catches 13090 loads and calls, and increases the
number of simple instructions CSE'd from 29658 to 36208.
llvm-svn: 122727
2011-01-03 03:18:43 +00:00
79d83067ee
rename InstValue to SimpleValue, add some comments.
...
llvm-svn: 122725
2011-01-03 02:20:48 +00:00
edb5bcdde5
CMake: Add missing source file.
...
llvm-svn: 122724
2011-01-03 02:13:05 +00:00
d815f69b30
Allocate nodes for the scoped hash table from a recyling bump pointer
...
allocator. This speeds up early cse by about 20%
llvm-svn: 122723
2011-01-03 01:42:46 +00:00
02a9776b64
reduce redundancy in the hashing code and other misc cleanups.
...
llvm-svn: 122720
2011-01-03 01:10:08 +00:00
cab9a0abab
Add a new loop-instsimplify pass, with the intention of replacing the instance
...
of instcombine that is currently in the middle of the loop pass pipeline. This
commit only checks in the pass; it will hopefully be enabled by default later.
llvm-svn: 122719
2011-01-03 00:25:16 +00:00
0844c76f9a
fix some pastos
...
llvm-svn: 122718
2011-01-02 23:29:58 +00:00
8fac5db251
add DEBUG and -stats output to earlycse.
...
Teach it to CSE the rest of the non-side-effecting instructions.
llvm-svn: 122716
2011-01-02 23:19:45 +00:00
18ae5436b1
Enhance earlycse to do CSE of casts, instsimplify and die.
...
Add a testcase.
llvm-svn: 122715
2011-01-02 23:04:14 +00:00
bf0aa927cc
split dom frontier handling stuff out to its own DominanceFrontier header,
...
so that Dominators.h is *just* domtree. Also prune #includes a bit.
llvm-svn: 122714
2011-01-02 22:09:33 +00:00
704541bb23
sketch out a new early cse pass. No functionality yet.
...
llvm-svn: 122713
2011-01-02 21:47:05 +00:00
9c69406f2b
fix a miscompilation of tramp3d-v4: when forming a memcpy, we have to make
...
sure that the loop we're promoting into a memcpy doesn't mutate the input
of the memcpy. Before we were just checking that the dest of the memcpy
wasn't mod/ref'd by the loop.
llvm-svn: 122712
2011-01-02 21:14:18 +00:00
5702a43c09
If a loop iterates exactly once (has backedge count = 0) then don't
...
mess with it. We'd rather peel/unroll it than convert all of its
stores into memsets.
llvm-svn: 122711
2011-01-02 20:24:21 +00:00
5361b84184
Also remove functions that use complex constant expressions in terms of
...
another function.
llvm-svn: 122705
2011-01-02 19:16:44 +00:00
8455b6e45e
enhance loop idiom recognition to scan *all* unconditionally executed
...
blocks in a loop, instead of just the header block. This makes it more
aggressive, able to handle Duncan's Ada examples.
llvm-svn: 122704
2011-01-02 19:01:03 +00:00
0cdc6f62a5
make inSubLoop much more efficient.
...
llvm-svn: 122703
2011-01-02 18:53:08 +00:00
27497ece96
rip out isExitBlockDominatedByBlockInLoop, calling DomTree::dominates instead.
...
isExitBlockDominatedByBlockInLoop is a relic of the days when domtree was
*just* a tree and didn't have DFS numbers. Checking DFS numbers is faster
and easier than "limiting the search of the tree".
llvm-svn: 122702
2011-01-02 18:45:39 +00:00
0469e01c02
add a list of opportunities for future improvement.
...
llvm-svn: 122701
2011-01-02 18:32:09 +00:00
64f1c0dcda
Fix PR8702 by not having LoopSimplify claim to preserve LCSSA form. As described
...
in the PR, the pass could break LCSSA form when inserting preheaders. It probably
would be easy enough to fix this, but since currently we always go into LCSSA form
after running this pass, doing so is not urgent.
llvm-svn: 122695
2011-01-02 13:38:21 +00:00
ddf58010bd
Allow loop-idiom to run on multiple BB loops, but still only scan the loop
...
header for now for memset/memcpy opportunities. It turns out that loop-rotate
is successfully rotating loops, but *DOESN'T MERGE THE BLOCKS*, turning "for
loops" into 2 basic block loops that loop-idiom was ignoring.
With this fix, we form many *many* more memcpy and memsets than before, including
on the "history" loops in the viterbi benchmark, which look like this:
for (j=0; j<MAX_history; ++j) {
history_new[i][j+1] = history[2*i][j];
}
Transforming these loops into memcpy's speeds up the viterbi benchmark from
11.98s to 3.55s on my machine. Woo.
llvm-svn: 122685
2011-01-02 07:58:36 +00:00
5b5a043d82
remove debugging code.
...
llvm-svn: 122683
2011-01-02 07:37:13 +00:00
12f91befce
add some -stats output.
...
llvm-svn: 122682
2011-01-02 07:36:44 +00:00
679572e584
improve loop rotation to use CodeMetrics to analyze the
...
size of a loop header instead of its own code size estimator.
This allows it to handle bitcasts etc more precisely.
llvm-svn: 122681
2011-01-02 07:35:53 +00:00
85b6d81d41
teach loop idiom recognition to form memcpy's from simple loops.
...
llvm-svn: 122678
2011-01-02 03:37:56 +00:00
4e250c8245
Remove functions from the FnSet when one of their callee's is being merged. This
...
maintains the guarantee that the DenseSet expects two elements it contains to
not go from inequal to equal under its nose.
As a side-effect, this also lets us switch from iterating to a fixed-point to
actually maintaining a work queue of functions to look at again, and we don't
add thunks to our work queue so we don't need to detect and ignore them.
llvm-svn: 122677
2011-01-02 02:46:33 +00:00
1903c42b97
fix a globalopt crash on two Adobe-C++ testcases that the recent
...
loop idiom pass exposed.
llvm-svn: 122674
2011-01-01 22:31:46 +00:00
a3514441e0
add a validity check that was missed, fixing a crash on the
...
new testcase.
llvm-svn: 122662
2011-01-01 20:12:04 +00:00
91a4435875
improve validity check to handle constant-trip-count loops more
...
aggressively. In practice, this doesn't help anything though,
see the todo.
llvm-svn: 122660
2011-01-01 19:54:22 +00:00
8b3baf6d75
implement the "no aliasing accesses in loop" safety check. This pass
...
should be correct now.
llvm-svn: 122659
2011-01-01 19:39:01 +00:00
2c440fa403
Simplify this pass by using a depth-first iterator to ensure that all
...
operands are visited before the instructions themselves.
llvm-svn: 122647
2010-12-31 17:49:05 +00:00
6cc7126ed9
Zap dead instructions harder.
...
llvm-svn: 122645
2010-12-31 16:17:54 +00:00
570dd787a6
Make a bunch of symbols internal.
...
llvm-svn: 122642
2010-12-30 22:34:44 +00:00
65a699d4d0
simplify this, isBytewiseValue handles the extra check. We still
...
check for "multiple of a byte" in size to make it clear that the
>> 3 below is safe.
llvm-svn: 122604
2010-12-28 18:53:48 +00:00
5cf10e691b
Silence gcc warning about an unused variable when doing a release build.
...
llvm-svn: 122593
2010-12-28 09:41:15 +00:00
cb18bfa3d2
fix some issues Frits noticed, add AliasAnalysis as a dependency
...
llvm-svn: 122585
2010-12-27 18:39:08 +00:00
84bd73c527
BuildLibCalls: Nuke EmitMemCpy, EmitMemMove and EmitMemSet. They are dead and superseded by IRBuilder.
...
llvm-svn: 122576
2010-12-27 00:25:32 +00:00
7cba269dfb
SimplifyLibCalls: Use IRBuilder to simplify code.
...
llvm-svn: 122575
2010-12-27 00:16:46 +00:00
b9fe685b9a
have loop-idiom nuke instructions that feed stores that get removed.
...
llvm-svn: 122574
2010-12-27 00:03:23 +00:00
29e14edc8d
implement enough of the memset inference algorithm to recognize and insert
...
memsets. This is still missing one important validity check, but this is enough
to compile stuff like this:
void test0(std::vector<char> &X) {
for (std::vector<char>::iterator I = X.begin(), E = X.end(); I != E; ++I)
*I = 0;
}
void test1(std::vector<int> &X) {
for (long i = 0, e = X.size(); i != e; ++i)
X[i] = 0x01010101;
}
With:
$ clang t.cpp -S -o - -O2 -emit-llvm | opt -loop-idiom | opt -O3 | llc
to:
__Z5test0RSt6vectorIcSaIcEE: ## @_Z5test0RSt6vectorIcSaIcEE
## BB#0: ## %entry
subq $8, %rsp
movq (%rdi), %rax
movq 8(%rdi), %rsi
cmpq %rsi, %rax
je LBB0_2
## BB#1: ## %bb.nph
subq %rax, %rsi
movq %rax, %rdi
callq ___bzero
LBB0_2: ## %for.end
addq $8, %rsp
ret
...
__Z5test1RSt6vectorIiSaIiEE: ## @_Z5test1RSt6vectorIiSaIiEE
## BB#0: ## %entry
subq $8, %rsp
movq (%rdi), %rax
movq 8(%rdi), %rdx
subq %rax, %rdx
cmpq $4, %rdx
jb LBB1_2
## BB#1: ## %for.body.preheader
andq $-4, %rdx
movl $1, %esi
movq %rax, %rdi
callq _memset
LBB1_2: ## %for.end
addq $8, %rsp
ret
llvm-svn: 122573
2010-12-26 23:42:51 +00:00
6cf8d6cc6e
start using irbuilder to make mem intrinsics in a few passes.
...
llvm-svn: 122572
2010-12-26 22:57:41 +00:00
7c5f9c35d1
sketch more of this out.
...
llvm-svn: 122567
2010-12-26 20:45:45 +00:00
9cb1035f94
move isBytewiseValue out to ValueTracking.h/cpp
...
llvm-svn: 122565
2010-12-26 20:15:01 +00:00
81ae3f299a
actually add the file...
...
llvm-svn: 122563
2010-12-26 19:39:38 +00:00
2ef535a4e4
Start of a pass for recognizing memset and memcpy idioms.
...
No functionality yet.
llvm-svn: 122562
2010-12-26 19:32:44 +00:00
30342fb1fd
Simplify code.
...
llvm-svn: 122561
2010-12-26 15:23:45 +00:00
d729d0dcdb
don't lose TD info
...
llvm-svn: 122556
2010-12-25 20:52:04 +00:00
20fca48341
switch the inliner alignment enforcement stuff to use the
...
getOrEnforceKnownAlignment function, which simplifies the code
and makes it stronger.
llvm-svn: 122555
2010-12-25 20:42:38 +00:00
6fcd32e7d7
Move getOrEnforceKnownAlignment out of instcombine into Transforms/Utils.
...
llvm-svn: 122554
2010-12-25 20:37:57 +00:00
b90b2f0635
Fix a thinko pointed out by Frits van Bommel: looking through global variables in isBytewiseValue is not safe.
...
llvm-svn: 122550
2010-12-24 22:23:59 +00:00
ea9152e551
MemCpyOpt: Turn memcpys from a constant into a memset if possible.
...
This allows us to compile "int cst[] = {-1, -1, -1};" into
movl $-1, 16(%rsp)
movq $-1, 8(%rsp)
instead of
movl _cst+8(%rip), %eax
movl %eax, 16(%rsp)
movq _cst(%rip), %rax
movq %rax, 8(%rsp)
llvm-svn: 122548
2010-12-24 21:17:12 +00:00
226ac14afb
When determining if we can fold (x >> C1) << C2, the bits that we need to verify are zero
...
are not the low bits of x, but the bits that WILL be the low bits after the operation completes.
llvm-svn: 122529
2010-12-23 23:56:24 +00:00
5d690d4168
It is possible for SimplifyCFG to cause PHI nodes to become redundant too late in the optimization
...
pipeline to be caught by instcombine, and it's not feasible to catch them in SimplifyCFG because the
use-lists are in an inconsistent state at the point where it could know that it need to simplify them.
Instead, have CodeGenPrepare look for trivially redundant PHIs as part of its general cleanup effort.
llvm-svn: 122516
2010-12-23 20:57:35 +00:00
18b762a946
Preserve the address space when generating bitcasts for MemTransferInst in ConvertToScalarInfo
...
llvm-svn: 122462
2010-12-23 01:41:32 +00:00
9b43f33620
Change all self assignments X=X to (void)X, so that we can turn on a
...
new gcc warning that complains on self-assignments and
self-initializations.
llvm-svn: 122458
2010-12-23 00:58:24 +00:00
8ef5001b27
InstCombine: creating selects from -1 and 0 is fine, they combine into a sext from i1.
...
llvm-svn: 122453
2010-12-22 23:12:15 +00:00
fbb9ac3cca
Add a generic expansion transform: A op (B op' C) -> (A op B) op' (A op C)
...
if both A op B and A op C simplify. This fires fairly often but doesn't
make that much difference. On gcc-as-one-file it removes two "and"s and
turns one branch into a select.
llvm-svn: 122399
2010-12-22 13:36:08 +00:00
3547d2ebd8
Add some statistics, good for understanding how much more powerful
...
instcombine is compared to instsimplify.
llvm-svn: 122397
2010-12-22 09:40:51 +00:00
5ab8d4b5e5
Give GVN back the ability to perform simple conditional propagation on conditional branch values.
...
I still think that LVI should be handling this, but that capability is some ways off in the future,
and this matters for some significant benchmarks.
llvm-svn: 122378
2010-12-21 23:54:34 +00:00
12470778d7
Remove dead code.
...
llvm-svn: 122371
2010-12-21 22:31:24 +00:00
43493c089f
GVN's Expression is not POD-like (it contains a SmallVector). Simplify code while at it.
...
llvm-svn: 122362
2010-12-21 21:30:19 +00:00
3b8af41a3e
Visit instructions deterministically. Use a FIFO so as to approximately
...
visit instructions before their uses, since InstructionSimplify does a
better job in that case. All this prompted by Frits van Bommel.
llvm-svn: 122343
2010-12-21 17:08:55 +00:00
e7cbb64ec0
If an instruction simplifies, try again to simplify any uses of it. This is
...
not very important since the pass is only used for testing, but it does make
it more realistic. Suggested by Frits van Bommel.
llvm-svn: 122336
2010-12-21 16:12:03 +00:00
d0eb6d39f8
Pull a few more simplifications out of instcombine (there are still
...
plenty left though!), in particular for multiplication.
llvm-svn: 122330
2010-12-21 14:00:22 +00:00
eaff500c7b
Oops, forgot to add the pass itself!
...
llvm-svn: 122265
2010-12-20 21:07:42 +00:00
a436cbe4bf
Add a new convenience pass for testing InstructionSimplify. Previously
...
it could only be tested indirectly, via instcombine, gvn or some other
pass that makes use of InstructionSimplify, which means that testcases
had to be carefully contrived to dance around any other transformations
that that pass did.
llvm-svn: 122264
2010-12-20 20:54:37 +00:00
f7957d0463
Add a check missing from my last commit and avoid a potential overflow situation.
...
llvm-svn: 122258
2010-12-20 20:00:31 +00:00
2bca3a67b3
Reduce indentation.
...
llvm-svn: 122249
2010-12-20 16:21:59 +00:00
68531baea9
Teach InstCombine to merge (icmp ult (X + CA), C1) | (icmp eq X, C2) into (icmp ult (X + CA), C1 + 1) if C2 + CA == C1.
...
InstCombine creates these so now we compile x == 23 || x == 24 || x == 25 to
%x.off = add i32 %x, -23
%1 = icmp ult i32 %x.off, 3
instead of
%x.off = add i32 %x, -23
%1 = icmp ult i32 %x.off, 2
%cmp3 = icmp eq i32 %x, 25
%ret2 = or i1 %1, %cmp3
llvm-svn: 122248
2010-12-20 16:18:51 +00:00
27ca8ebd4b
fix PR8807 by making transformConstExprCastCall aware of byval arguments.
...
llvm-svn: 122238
2010-12-20 08:36:38 +00:00
7398965b67
various cleanups for transformConstExprCastCall
...
llvm-svn: 122237
2010-12-20 08:25:06 +00:00
0f11495289
when eliding a byval copy due to inlining a readonly function, we have
...
to make sure that the reused alloca has sufficient alignment.
llvm-svn: 122236
2010-12-20 08:10:40 +00:00
0099744506
pull byval processing out to its own helper function.
...
llvm-svn: 122235
2010-12-20 07:57:41 +00:00
7394680a00
fix PR8769, a miscompilation by inliner when inlining a function with a byval
...
argument. The generated alloca has to have at least the alignment of the
byval, if not, the client may be making assumptions that the new alloca won't
satisfy.
llvm-svn: 122234
2010-12-20 07:45:28 +00:00
1991c47ec1
Avoid dropping the address space when InstCombine optimizes memset
...
llvm-svn: 122215
2010-12-20 01:05:30 +00:00
4fb9dd4c74
fix an oversight caught by Frits!
...
llvm-svn: 122204
2010-12-19 23:24:04 +00:00
b6252a376a
tidy up
...
llvm-svn: 122190
2010-12-19 20:24:28 +00:00
3e635d2e99
move a transformation to a more logical place, simplifying it.
...
llvm-svn: 122183
2010-12-19 19:43:52 +00:00
5e0c0c72e9
recognize an unsigned add with overflow idiom into uadd.
...
This resolves a README entry and technically resolves PR4916,
but we still get poor code for the testcase in that PR because
GVN isn't CSE'ing uadd with add, filed as PR8817.
Previously we got:
_test7: ## @test7
addq %rsi, %rdi
cmpq %rdi, %rsi
movl $42, %eax
cmovaq %rsi, %rax
ret
Now we get:
_test7: ## @test7
addq %rsi, %rdi
movl $42, %eax
cmovbq %rsi, %rax
ret
llvm-svn: 122182
2010-12-19 19:37:52 +00:00
33dc3f0cfa
optimize uadd(x, cst) into a comparison when the normal
...
result is dead. This is required for my next patch to not
regress the testsuite.
llvm-svn: 122181
2010-12-19 19:35:32 +00:00
ce2995ae58
use IC.ReplaceInstUsesWith instead of a raw RAUW so that uses of
...
the old thing end up on the instcombine worklist. Not doing this
can cause an extra top-level iteration of instcombine, burning
compile time.
llvm-svn: 122179
2010-12-19 18:38:44 +00:00
79874566ce
generalize the sadd creation code to not require that the
...
sadd formed is half the size of the original type. We can
now compile this into a sadd.i8:
unsigned char X(char a, char b) {
int res = a+b;
if ((unsigned )(res+128) > 255U)
abort();
return res;
}
llvm-svn: 122178
2010-12-19 18:35:09 +00:00
c56c845377
fix another miscompile in the llvm.sadd formation logic: it wasn't
...
checking to see if the high bits of the original add result were dead.
Inserting a smaller add and zexting back to that size is not good enough.
This is likely to be the fix for 8816.
llvm-svn: 122177
2010-12-19 18:22:06 +00:00
f29562db25
fix a bug (possibly 8816) in the sadd forming xform: it isn't
...
profitable (or safe) to promote code when the add-with-constant
has other uses.
llvm-svn: 122175
2010-12-19 17:59:02 +00:00
ee61c1d820
rework the code added in r122072 to pull it out to its own
...
helper function, clean up comments, and reduce indentation.
No functionality change.
llvm-svn: 122174
2010-12-19 17:52:50 +00:00
408a684d29
Enhance LICM to promote alias sets whose pointers themselves are stored,
...
which doesn't affect the memory address being promoted.
llvm-svn: 122172
2010-12-19 05:57:25 +00:00
3337a81450
fix PR8602, a bug in an assertion: a volatile store *of* a pointer
...
does not make the alias set for that pointer volatile, just stores
*to* the pointer.
llvm-svn: 122171
2010-12-19 05:51:54 +00:00
fb888622c3
revert r122164, I'm going to go with a different approach.
...
llvm-svn: 122168
2010-12-19 04:23:03 +00:00
583ec6fa44
first step to fixing PR8642: don't fold away empty basic blocks
...
which have trapping constant exprs in them due to PHI nodes.
Eliminating them can cause the constant expr to be evalutated
on new paths if the input edges are critical.
llvm-svn: 122164
2010-12-19 03:02:34 +00:00
6b8b4855ff
simplify this a bit.
...
llvm-svn: 122156
2010-12-18 20:22:49 +00:00
5e3605552e
Whitespace fixes. No functionality change.
...
llvm-svn: 122110
2010-12-17 23:27:41 +00:00
7aa18bf46a
Add vector versions of some existing scalar transforms to aid codegen in matching psign & pblend operations to the IR produced by clang/gcc for their C idioms.
...
llvm-svn: 122105
2010-12-17 23:12:19 +00:00
1294ea7d53
Reapply r121905 (automatic synthesis of @llvm.sadd.with.overflow) with a fix for a bug that manifested itself
...
on the DragonEgg self-host bot. Unfortunately, the testcase is pretty messy and doesn't reduce well due to
interactions with other parts of InstCombine.
llvm-svn: 122072
2010-12-17 18:08:00 +00:00
e5f49c4ff2
SimplifyCFG: Ranges can be larger than 64 bits. Fixes Release-selfhost build.
...
llvm-svn: 122054
2010-12-17 10:48:14 +00:00
d14b0f1db7
improve switch formation to handle small range
...
comparisons formed by comparisons. For example,
this:
void foo(unsigned x) {
if (x == 0 || x == 1 || x == 3 || x == 4 || x == 6)
bar();
}
compiles into:
_foo: ## @foo
## BB#0: ## %entry
cmpl $6, %edi
ja LBB0_2
## BB#1: ## %entry
movl %edi, %eax
movl $91, %ecx
btq %rax, %rcx
jb LBB0_3
instead of:
_foo: ## @foo
## BB#0: ## %entry
cmpl $2, %edi
jb LBB0_4
## BB#1: ## %switch.early.test
cmpl $6, %edi
ja LBB0_3
## BB#2: ## %switch.early.test
movl %edi, %eax
movl $88, %ecx
btq %rax, %rcx
jb LBB0_4
This catches a bunch of cases in GCC, which look like this:
%804 = load i32* @which_alternative, align 4, !tbaa !0
%805 = icmp ult i32 %804, 2
%806 = icmp eq i32 %804, 3
%or.cond121 = or i1 %805, %806
%807 = icmp eq i32 %804, 4
%or.cond124 = or i1 %or.cond121, %807
br i1 %or.cond124, label %.thread, label %808
turning this into a range comparison.
llvm-svn: 122045
2010-12-17 06:20:15 +00:00
93dc2b808f
Revert r64460. strtol and friends cannot be marked readonly, even with
...
a null endptr argument, because they may write to errno.
This fixes a seflhost miscompile observed on Linux targets when TBAA
was enabled.
llvm-svn: 122014
2010-12-17 01:09:43 +00:00
9bbe849fc3
Fix a bug in the loop in JumpThreading::ProcessThreadableEdges() where it could falsely produce a MultipleDestSentinel value if the first predecessor ended with an 'indirectbr'. If that happened, it caused an unnecessary FindMostPopularDest() call.
...
This wasn't a correctness problem, but it broke the fast path for single-predecessor blocks.
llvm-svn: 121966
2010-12-16 12:16:00 +00:00
8d1ab6f6e1
Speculatively revert commit 121905 since it looks like it might have broken the
...
dragonegg self-host buildbot. Original commit message:
Add an InstCombine transform to recognize instances of manual overflow-safe addition
(performing the addition in a wider type and explicitly checking for overflow), and
fold them down to intrinsics. This currently only supports signed-addition, but could
be generalized if someone works out the magic constant formulas for other operations.
llvm-svn: 121965
2010-12-16 09:40:54 +00:00
e1a17a3473
Make memcpyopt TBAA-aware.
...
llvm-svn: 121944
2010-12-16 02:51:19 +00:00
4467aa5294
Preserve TBAA tags when doing load PRE.
...
llvm-svn: 121921
2010-12-15 23:53:55 +00:00
1cf8881299
Add an InstCombine transform to recognize instances of manual overflow-safe addition
...
(performing the addition in a wider type and explicitly checking for overflow), and
fold them down to intrinsics. This currently only supports signed-addition, but could
be generalized if someone works out the magic constant formulas for other operations.
Fixes <rdar://problem/8558713>.
llvm-svn: 121905
2010-12-15 22:32:38 +00:00
a4fcd2418d
Move Value::getUnderlyingObject to be a standalone
...
function so that it can live in Analysis instead of
VMCore.
llvm-svn: 121885
2010-12-15 20:02:24 +00:00
0a2c416894
Move Sub simplifications and additional Add simplifications out of
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instcombine and into InstructionSimplify.
llvm-svn: 121861
2010-12-15 14:07:39 +00:00
3d1803495e
Teach jump threading to "look through" a select when the branch direction of a terminator depends on it.
...
When it sees a promising select it now tries to figure out whether the condition of the select is known in any of the predecessors and if so it maps the operands appropriately.
llvm-svn: 121859
2010-12-15 09:51:20 +00:00
e893e2601e
make qsort predicate more conformant by returning 0 for equal values.
...
llvm-svn: 121838
2010-12-15 04:52:41 +00:00
35609d97ae
Fix PR8790, another instance where unreachable code can cause instruction simplification to fail,
...
this case involve a select that simplifies to itself.
llvm-svn: 121817
2010-12-15 00:55:35 +00:00
15c85c916f
Cleanup trailing whitespace.
...
llvm-svn: 121816
2010-12-15 00:52:44 +00:00
7499b452c1
- Insert new instructions before DomBlock's terminator,
...
which is simpler than finding a place to insert in BB.
- Don't perform the 'if condition hoisting' xform on certain
i1 PHIs, as it interferes with switch formation.
This re-fixes "example 7", without breaking the world hopefully.
llvm-svn: 121764
2010-12-14 08:46:09 +00:00
335f0e4ad4
fix two significant issues with FoldTwoEntryPHINode:
...
first, it can kick in on blocks whose conditions have been
folded to a constant, even though one of the edges will be
trivially folded.
second, it doesn't clean up the "if diamond" that it just
eliminated away. This is a problem because other simplifycfg
xforms kick in depending on the order of block visitation,
causing pointless work.
llvm-svn: 121762
2010-12-14 08:01:53 +00:00
dc20a7d38c
remove the instsimplify logic I added in r121754. It is apparently
...
breaking the selfhost builds, though I can't fathom how.
llvm-svn: 121761
2010-12-14 07:53:03 +00:00
9ac168d0ab
clean up logic, convert std::set to SmallPtrSet, handle the case
...
when all 2-entry phis are simplified away.
llvm-svn: 121760
2010-12-14 07:41:39 +00:00
9fd838d31b
tidy up a bit, move DEBUG down to when we commit to doing the transform so we
...
don't print it unless the xform happens.
llvm-svn: 121758
2010-12-14 07:23:10 +00:00
b42d293faa
use SimplifyInstruction instead of reimplementing part of it.
...
llvm-svn: 121757
2010-12-14 07:20:29 +00:00
fb73de482c
simplify GetIfCondition by using getSinglePredecessor.
...
llvm-svn: 121756
2010-12-14 07:15:21 +00:00
0f4d67bd88
use AddPredecessorToBlock in 3 places instead of a manual loop.
...
llvm-svn: 121755
2010-12-14 07:09:42 +00:00
a07cc6f4fd
make FoldTwoEntryPHINode use instsimplify a bit, make
...
GetIfCondition faster by avoiding pred_iterator. No
really interesting change.
llvm-svn: 121754
2010-12-14 07:00:00 +00:00
afd2a8cfbb
remove the dead (and terrible) llvm::RemoveSuccessor function.
...
llvm-svn: 121753
2010-12-14 06:51:55 +00:00
d7beca3782
improve DEBUG's a bit, switch to eraseFromParent() to simplify
...
code a bit, switch from constant folding to instsimplify.
llvm-svn: 121751
2010-12-14 06:17:25 +00:00
5a9d59d918
reapply my recent change that disables a piece of the switch formation
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work, but fixes 400.perlbmk.
llvm-svn: 121749
2010-12-14 05:57:30 +00:00
3e5648896e
Fix recent buildbot breakage by pulling SimplifyCFG back to its state as of r121694, the most recent state
...
where I'm confident there were no crashes or miscompilations. XFAIL the test added since then for now.
llvm-svn: 121733
2010-12-13 23:49:28 +00:00
a6e5d5694a
temporarily disable part of my previous patch, which causes an iterator invalidation issue, causing a crash on some versions of perlbmk.
...
llvm-svn: 121728
2010-12-13 23:02:19 +00:00
2d434e594e
add some DEBUG's.
...
llvm-svn: 121711
2010-12-13 19:55:30 +00:00
1e155ab7e1
Fix sort predicate. qsort(3)'s predicate semantics differ from std::sort's. Fixes PR 8780.
...
llvm-svn: 121705
2010-12-13 18:20:38 +00:00
fb836f8c1a
reinstate my patch: the miscompile was caused by an inverted branch in the
...
'and' case.
llvm-svn: 121695
2010-12-13 08:12:19 +00:00
79db357d80
Completely disable the optimization I added in r121680 until
...
I can track down a miscompile. This should bring the buildbots
back to life
llvm-svn: 121693
2010-12-13 07:41:29 +00:00
fbeb55844b
Make simplifycfg reprocess newly formed "br (cond1 | cond2)" conditions
...
when simplifying, allowing them to be eagerly turned into switches. This
is the last step required to get "Example 7" from this blog post:
http://blog.regehr.org/archives/320
On X86, we now generate this machine code, which (to my eye) seems better
than the ICC generated code:
_crud: ## @crud
## BB#0: ## %entry
cmpb $33, %dil
jb LBB0_4
## BB#1: ## %switch.early.test
addb $-34, %dil
cmpb $58, %dil
ja LBB0_3
## BB#2: ## %switch.early.test
movzbl %dil, %eax
movabsq $288230376537592865, %rcx ## imm = 0x400000017001421
btq %rax, %rcx
jb LBB0_4
LBB0_3: ## %lor.rhs
xorl %eax, %eax
ret
LBB0_4: ## %lor.end
movl $1, %eax
ret
llvm-svn: 121690
2010-12-13 07:00:06 +00:00
1d05761df4
make this logic a bit simpler.
...
llvm-svn: 121689
2010-12-13 06:36:51 +00:00
25c3af35d8
split all the guts of SimplifyCFGOpt::run out into one function
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per terminator kind.
llvm-svn: 121688
2010-12-13 06:25:44 +00:00
cb570f87e5
fix a bug in r121680 that upset the various buildbots.
...
llvm-svn: 121687
2010-12-13 05:34:18 +00:00
a6db741f3d
refactor the speculative execution logic to be factored into the cond branch code instead of
...
doing a cfg search for every block simplified.
llvm-svn: 121686
2010-12-13 05:26:52 +00:00
466f54ffcf
simplify a bunch of code.
...
llvm-svn: 121685
2010-12-13 05:20:28 +00:00
6df7bdd810
move HoistThenElseCodeToIf up to a more logical and efficient-to-handle place.
...
llvm-svn: 121684
2010-12-13 05:15:29 +00:00
2e3832d9a0
move 'MergeBlocksIntoPredecessor' call earlier. Use
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getSinglePredecessor to simplify code.
llvm-svn: 121683
2010-12-13 05:10:48 +00:00
a69c443459
factor new code out to a SimplifyBranchOnICmpChain helper function.
...
llvm-svn: 121681
2010-12-13 05:03:41 +00:00
a442f24a36
enhance the "change or icmp's into switch" xform to handle one value in an
...
'or sequence' that it doesn't understand. This allows us to optimize
something insane like this:
int crud (unsigned char c, unsigned x)
{
if(((((((((( (int) c <= 32 ||
(int) c == 46) || (int) c == 44)
|| (int) c == 58) || (int) c == 59) || (int) c == 60)
|| (int) c == 62) || (int) c == 34) || (int) c == 92)
|| (int) c == 39) != 0)
foo();
}
into:
define i32 @crud(i8 zeroext %c, i32 %x) nounwind ssp noredzone {
entry:
%cmp = icmp ult i8 %c, 33
br i1 %cmp, label %if.then, label %switch.early.test
switch.early.test: ; preds = %entry
switch i8 %c, label %if.end [
i8 39, label %if.then
i8 44, label %if.then
i8 58, label %if.then
i8 59, label %if.then
i8 60, label %if.then
i8 62, label %if.then
i8 46, label %if.then
i8 92, label %if.then
i8 34, label %if.then
]
by pulling the < comparison out ahead of the newly formed switch.
llvm-svn: 121680
2010-12-13 04:50:38 +00:00
5a177e681e
merge two very similar functions into one that has a bool argument.
...
llvm-svn: 121678
2010-12-13 04:26:26 +00:00
9b1af510cb
don't bother handling non-canonical icmp's
...
llvm-svn: 121676
2010-12-13 04:18:32 +00:00
395252d93e
inline a function, making the result much simpler.
...
llvm-svn: 121675
2010-12-13 04:15:19 +00:00
62cc76e9cc
Fix my previous patch to handle a degenerate case that the llvm-gcc
...
bootstrap buildbot tripped over.
llvm-svn: 121674
2010-12-13 03:43:57 +00:00
11dafaa3ec
convert some methods to be static functions
...
llvm-svn: 121673
2010-12-13 03:30:12 +00:00
4642d79fb0
zap two more std::sorts.
...
llvm-svn: 121672
2010-12-13 03:24:30 +00:00
d9bacc088a
fix a fairly serious oversight with switch formation from
...
or'd conditions. Previously we'd compile something like this:
int crud (unsigned char c) {
return c == 62 || c == 34 || c == 92;
}
into:
switch i8 %c, label %lor.rhs [
i8 62, label %lor.end
i8 34, label %lor.end
]
lor.rhs: ; preds = %entry
%cmp8 = icmp eq i8 %c, 92
br label %lor.end
lor.end: ; preds = %entry, %entry, %lor.rhs
%0 = phi i1 [ true, %entry ], [ %cmp8, %lor.rhs ], [ true, %entry ]
%lor.ext = zext i1 %0 to i32
ret i32 %lor.ext
which failed to merge the compare-with-92 into the switch. With this patch
we simplify this all the way to:
switch i8 %c, label %lor.rhs [
i8 62, label %lor.end
i8 34, label %lor.end
i8 92, label %lor.end
]
lor.rhs: ; preds = %entry
br label %lor.end
lor.end: ; preds = %entry, %entry, %entry, %lor.rhs
%0 = phi i1 [ true, %entry ], [ false, %lor.rhs ], [ true, %entry ], [ true, %entry ]
%lor.ext = zext i1 %0 to i32
ret i32 %lor.ext
which is much better for codegen's switch lowering stuff. This kicks in 33 times
on 176.gcc (for example) cutting 103 instructions off the generated code.
llvm-svn: 121671
2010-12-13 03:18:54 +00:00
73a58627c3
simplify code and reduce indentation
...
llvm-svn: 121670
2010-12-13 02:38:13 +00:00
7c8e6047d6
convert an std::sort to array_pod_sort.
...
llvm-svn: 121669
2010-12-13 02:00:58 +00:00
1475987634
move the "br (X == 0 | X == 1), T, F" -> switch optimization to a new
...
location in simplifycfg. In the old days, SimplifyCFG was never run on
the entry block, so we had to scan over all preds of the BB passed into
simplifycfg to do this xform, now we can just check blocks ending with
a condbranch. This avoids a scan over all preds of every simplified
block, which should be a significant compile-time perf win on functions
with lots of edges. No functionality change.
llvm-svn: 121668
2010-12-13 01:57:34 +00:00
4088e2b8e4
reduce indentation and generally simplify code, no functionality change.
...
llvm-svn: 121667
2010-12-13 01:47:07 +00:00
7cb7867d7a
use getFirstNonPHIOrDbg to simplify this code.
...
llvm-svn: 121664
2010-12-13 01:28:06 +00:00
c4169cebe3
Generalize the and-icmp-select instcombine further by allowing selects of the form
...
(x & 2^n) ? 2^m+C : C
we can offset both arms by C to get the "(x & 2^n) ? 2^m : 0" form, optimize the
select to a shift and apply the offset afterwards.
llvm-svn: 121609
2010-12-11 10:49:22 +00:00
c8b035d006
Factor the (x & 2^n) ? 2^m : 0 instcombine into its own method and generalize it
...
to catch cases where n != m with a shift.
llvm-svn: 121608
2010-12-11 09:42:59 +00:00
bc4457e317
enhance memcpyopt to zap memcpy's that have the same src/dst.
...
llvm-svn: 121362
2010-12-09 07:45:45 +00:00
fd51c52ef6
fix PR8753, eliminating a case where we'd infinitely make a
...
substitution because it doesn't actually change the IR. Patch by
Jakub Staszak!
llvm-svn: 121361
2010-12-09 07:39:50 +00:00
a32986e899
Really check that the bits that will become zero are actually already zero
...
before eliminating the operation that zeros them. This fixes rdar://8739316.
llvm-svn: 121353
2010-12-09 02:52:17 +00:00
d2f4b09e10
Remove some dead code from the jump threading pass.
...
The last uses of these functions were removed in r113852 when LazyValueInfo was permanently enabled and removed the need for them.
llvm-svn: 121133
2010-12-07 13:08:07 +00:00
583abbc4df
PR5207: Change APInt methods trunc(), sext(), zext(), sextOrTrunc() and
...
zextOrTrunc(), and APSInt methods extend(), extOrTrunc() and new method
trunc(), to be const and to return a new value instead of modifying the
object in place.
llvm-svn: 121120
2010-12-07 08:25:19 +00:00
0d71c4f564
reapply r121100 with a tweak to constant fold ConstExprs with TargetData
...
(if available) as we go so that we get simple constantexprs not insane ones.
This fixes the failure of clang/test/CodeGenCXX/virtual-base-ctor.cpp
that the previous iteration of this patch had.
llvm-svn: 121111
2010-12-07 04:33:29 +00:00
f10dcfb9fb
Temporarily revert r121100 as it's causing clang to fail
...
CodeGenCXX/virtual-base-ctor.cpp.
llvm-svn: 121102
2010-12-07 02:41:11 +00:00
287f4366c1
fix PR8710 - teach global opt that some constantexprs are too complex to
...
put in a global variable's initializer.
llvm-svn: 121100
2010-12-07 01:59:32 +00:00
d9df6eaa9c
Implement jump threading of 'indirectbr' by keeping track of whether we're looking for ConstantInt*s or BlockAddress*s.
...
llvm-svn: 121066
2010-12-06 23:36:56 +00:00
7ff0ba41bd
replace a linear scan with a symtab lookup, reduce indentation.
...
No functionality change.
llvm-svn: 121042
2010-12-06 21:53:07 +00:00
4dc53e37d9
Use a stronger predicate here, pointed out by Duncan
...
llvm-svn: 121040
2010-12-06 21:48:10 +00:00
ca335e38cf
add some DEBUG statements.
...
llvm-svn: 121038
2010-12-06 21:13:51 +00:00
fb212de06d
Fix PR8735, a really terrible problem in the inliner's "alloca merging"
...
optimization.
Consider:
static void foo() {
A = alloca
...
}
static void bar() {
B = alloca
...
call foo();
}
void main() {
bar()
}
The inliner proceeds bottom up, but lets pretend it decides not to inline foo
into bar. When it gets to main, it inlines bar into main(), and says "hey, I
just inlined an alloca "B" into main, lets remember that. Then it keeps going
and finds that it now contains a call to foo. It decides to inline foo into
main, and says "hey, foo has an alloca A, and I have an alloca B from another
inlined call site, lets reuse it". The problem with this of course, is that
the lifetime of A and B are nested, not disjoint.
Unfortunately I can't create a reasonable testcase for this: the one in the
PR is both huge and extremely sensitive, because you minor tweaks end up
causing foo to get inlined into bar too early. We already have tests for the
basic alloca merging optimization and this does not break them.
llvm-svn: 120995
2010-12-06 07:52:42 +00:00
cd3af96a8f
improve comment
...
llvm-svn: 120994
2010-12-06 07:43:04 +00:00
5b6a865f2e
improve -debug output and comments a little.
...
llvm-svn: 120993
2010-12-06 07:38:40 +00:00
94fbdf3814
Fix PR8728, a miscompilation I recently introduced. When optimizing
...
memcpy's like:
memcpy(A, B)
memcpy(A, C)
we cannot delete the first memcpy as dead if A and C might be aliases.
If so, we actually get:
memcpy(A, B)
memcpy(A, A)
which is not correct to transform into:
memcpy(A, A)
This patch was heavily influenced by Jakub Staszak's patch in PR8728, thanks
Jakub!
llvm-svn: 120974
2010-12-06 01:48:06 +00:00
76244867cf
Refactor jump threading.
...
Should have no functional change other than the order of two transformations that are mutually-exclusive and the exact formatting of debug output.
Internally, it now stores the ConstantInt*s as Constant*s, and actual undef values instead of nulls.
llvm-svn: 120946
2010-12-05 19:06:41 +00:00
5e75ef4a8e
Remove trailing whitespace.
...
llvm-svn: 120945
2010-12-05 19:02:47 +00:00
8fb69ee805
Teach SimplifyCFG to turn
...
(indirectbr (select cond, blockaddress(@fn, BlockA),
blockaddress(@fn, BlockB)))
into
(br cond, BlockA, BlockB).
llvm-svn: 120943
2010-12-05 18:29:03 +00:00
25a5e4ca1f
PR5207: Rename overloaded APInt methods set(), clear(), flip() to
...
setAllBits(), setBit(unsigned), etc.
llvm-svn: 120564
2010-12-01 08:53:58 +00:00
1c577b54b0
fix a bozo bug I introduced in r119930, causing a miscompile of
...
20040709-1.c from the gcc testsuite. I was using the size of a
pointer instead of the pointee. This fixes rdar://8713376
llvm-svn: 120519
2010-12-01 01:24:55 +00:00
903add84d9
Enhance DSE to handle the variable index case in PR8657.
...
llvm-svn: 120498
2010-11-30 23:43:23 +00:00
c0f3379ae0
teach DSE to use GetPointerBaseWithConstantOffset to analyze
...
may-aliasing stores that partially overlap with different base
pointers. This implements PR6043 and the non-variable part of
PR8657
llvm-svn: 120485
2010-11-30 23:05:20 +00:00
e28618de59
move GetPointerBaseWithConstantOffset out of GVN into ValueTracking.h
...
llvm-svn: 120476
2010-11-30 22:25:26 +00:00
50162e3c2a
remove a fixed fixme
...
llvm-svn: 120474
2010-11-30 22:18:11 +00:00
6712251f41
Make DeleteDeadInstruction be a static function, move some code around.
...
llvm-svn: 120471
2010-11-30 21:58:14 +00:00
51d67ce2ff
switch RemoveAccessedObjects to use AliasAnalysis::Location to simplify
...
the code. We now get accurate sizes on Loads, though it surely doesn't
matter in practice.
llvm-svn: 120469
2010-11-30 21:47:58 +00:00
f80b39986f
two improvements to RemoveAccessedObjects:
...
1. if the underlying pointer passed in can be resolved
to any argument or alloca, then we don't need to scan.
Previously we would only avoid the scan if the alloca
or byval was actually considered dead.
2. The dead store processing code is itself completely
dead and didn't handle volatile stores right anyway,
so delete it. This allows simplifying the interface
to RemoveAccessedObjects.
llvm-svn: 120467
2010-11-30 21:38:30 +00:00
7fe08b67fa
remove the "undead" terminology, which is nonstandard and never
...
made sense to me. We now have a set of dead stack objects, and
they become live when loaded. Fix a theoretical problem where
we'd pass in the wrong pointer to the alias query.
llvm-svn: 120465
2010-11-30 21:32:12 +00:00
127818d746
move call handling in handleEndBlock up a bit, and simplify it.
...
If the call might read all the allocas, stop scanning early.
Convert a vector to smallvector, shrink SmallPtrSet to 16 instead
of 64 to avoid crazy linear scans.
llvm-svn: 120463
2010-11-30 21:18:46 +00:00
d3a58c8fa1
Avoid exponential growth of a table. It feels like
...
there should be a better way to do this. PR 8679.
llvm-svn: 120457
2010-11-30 20:23:21 +00:00
60a8b3dab8
various cleanups and code simplification
...
llvm-svn: 120454
2010-11-30 19:48:15 +00:00
51c28a93cc
make getPointerSize a static function. Add ivars to DSE for
...
AA and MD pass info instead of using getAnalysis<> all over.
llvm-svn: 120453
2010-11-30 19:34:42 +00:00
77d79fa25f
reduce indentation, clean up TD use a bit.
...
llvm-svn: 120452
2010-11-30 19:28:23 +00:00
b63ba73b1b
enhance isRemovable to refuse to delete volatile mem transfers
...
now that DSE hacks on them. This fixes a regression I introduced,
by generalizing DSE to hack on transfers.
llvm-svn: 120445
2010-11-30 19:12:10 +00:00
58b779e9c2
Rewrite the main DSE loop to be written in terms of reasoning
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about pairs of AA::Location's instead of looking for MemDep's
"Def" predicate. This is more powerful and general, handling
memset/memcpy/store all uniformly, and implementing PR8701 and
probably obsoleting parts of memcpyoptimizer.
This also fixes an obscure bug with init.trampoline and i8
stores, but I'm not surprised it hasn't been hit yet. Enhancing
init.trampoline to carry the size that it stores would allow
DSE to be much more aggressive about optimizing them.
llvm-svn: 120406
2010-11-30 07:23:21 +00:00
e3ea1cba79
Add a puts optimization that converts puts() to putchar('\n').
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llvm-svn: 120398
2010-11-30 06:19:18 +00:00
3590ef817c
rename a function and reduce some indentation, no functionality change.
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llvm-svn: 120391
2010-11-30 05:30:45 +00:00
b438ef236c
remove the pointless check of MemoryUseIntrinsic from
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is trivially dead, since these have side effects. This makes the
(misnamed) MemoryUseIntrinsic class dead, so remove it.
llvm-svn: 120382
2010-11-30 02:03:47 +00:00
2227a8a192
rename doesClobberMemory -> hasMemoryWrite to be more specific, and
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remove an actively-wrong comment.
llvm-svn: 120378
2010-11-30 01:37:52 +00:00
9d179d911d
clean up handling of 'free', detangling it from everything else.
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It can be seriously improved, but at least now it isn't intertwined
with the other logic.
llvm-svn: 120377
2010-11-30 01:28:33 +00:00
9a146372b5
Teach basicaa that memset's modref set is at worst "mod" and never
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contains "ref".
Enhance DSE to use a modref query instead of a store-specific hack
to generalize the "ignore may-alias stores" optimization to handle
memset and memcpy.
llvm-svn: 120368
2010-11-30 00:28:45 +00:00
c3c754f750
my previous patch would cause us to start deleting some volatile
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stores, fix and add a testcase.
llvm-svn: 120363
2010-11-30 00:12:39 +00:00
Chris Lattner